Extension publication helps farmers price corn silage

April 30, 2013

WEST LAFAYETTE, Ind. – As the price of corn goes, so goes
the price of corn silage. Knowing how the price of the former will affect the
price of the latter can translate into extra dollars in the pockets of farmers.

Purdue Extension has a new publication to help dairy
producers and corn silage growers determine those prices. Determining a Value for Corn Silage also contains an online Corn
Silage Crop Calculator. The publication, AS-611-W, is free and available at
https://mdc.itap.purdue.edu/item.asp?item_number=AS-611-W.

"Corn silage prices depend on the price of grain, and
there can be a huge variation in prices," said Tamilee Nennich, a Purdue
Extension dairy cattle nutrition specialist and one of the publication's
authors. "There are a wide variety of strategies out there with which we
can price corn silage."

Corn silage, a forage consisting of corn grain and
cornstalks harvested when the corn plant is still partially green, makes up
about 30 percent of the dry matter in an average dairy cow's diet. The forage
is a good source of fiber and energy for lactating cows.

The $40-$50 per ton that dairy farmers typically pay corn
growers for silage often turns into $50-$80 per ton once the dairy producer
harvests and transports the forage, and then places it in a silo for
fermentation and storage, Nennich said. The silage usually remains in storage
for months until it is ready to be fed to cows.

There are many issues dairy producers and corn silage
growers should consider when pricing silage. Buyers and sellers will come at it
from different perspectives, Nennich said. One such issue is moisture content.

"Corn silage should contain 65-68 percent moisture,
but the amount of actual feed dry matter varies and should be taken into
account," she said. "Determining the silage dry matter is necessary
for arriving at the actual amount of feed that is harvested from a field."

Grain yield is another consideration. A larger grain
harvest could portend a higher silage price.

"As a general rule of thumb, you can price silage by
multiplying the price of corn per bushel by a factor of somewhere between eight
and 10," Nennich said.

The Corn Silage Crop Calculator is a Microsoft Excel-based
program that comes in two parts. One part calculates silage price based on
silage yield from the field, while the other calculates silage price based on
corn grain price. Either part can be used to arrive at a price for corn silage.

In both spreadsheets the farmer will enter data such as
corn price per bushel, silage yield per acre or estimated grain yield, percent
of corn silage dry matter, harvest/hauling/storage cost and the estimated
amount of shrinkage during storage. Results appear as cost of corn silage value
per ton and the final cost of silage to producer.

"There are default values built into the calculator,
or a silage producer can adjust the values according to what they save in
harvesting, drying and storage costs," Nennich said. "The dairy
producer can make adjustments on what their cost would be to haul and harvest
the corn silage themselves, so that they can see how that affects the final
silage price at feeding."

Nennich hopes silage producers and their dairy producer
customers do the calculations together. "It can help them arrive at a
mutual agreement for corn silage," she said.

Determining a Value
for Corn Silage is co-authored by Kern Hendrix, a retired Purdue Extension
cattle specialist. The publication is among a series of five new dairy
management publications written or co-written by Nennich. All are free for
download. Others include: